Modeling gaseous emissions and dispersion of two major greenhouse gases from landfill sites in arid hot environment.

As waste production exponentially increases, landfill continues to be the common method of waste disposal. Landfills represent significant anthropogenic sources of methane (CH) and carbon dioxide (CO); the main constituents of greenhouse gases (GHGs) resultant from microbial decomposition of organic waste. In the present study, ISC-AERMOD dispersion model was employed to estimate the release and dispersion rates of CH and CO from major landfill sites across Kuwait under different seasonal conditions. Results revealed that dispersions of CH and CO were influenced by the dominant northwestern and southeastern wind directions and thus, the dispersion of CH and CO extended predominantly toward northeastern direction. In terms of seasonal variation, the maximum concentrations of CH and CO were detected in winter and spring seasons, close to the landfill zone, and the dispersion of CH and CO fluxes during winter and spring seasons was longer than that during summer and fall seasons. Consequently, residential areas close to the disposal sites were exposed to higher concentrations of CH and CO gases during winter and spring. The findings of this study can serve as the basis for selecting suitable landfill locations under desert climatic conditions as determined by the distances over which gaseous emissions can diffuse.